A screw conveyor used in a novel way for metal finishing was filed of even date by the Applicants of the present invention. A screw conveyor typically includes a casing which bounds a cavity for receiving material. An auger or screw mechanism having a helicoid-type blade is disposed axially in the chamber and rotates with respect to the casing. The helicoid-type blade of the conveyor acts as a continuous inclined plane for forcing material through the screw conveyor.
In some applications, no seal is required between the blade and the casing of the screw conveyor. In other applications, a seal is provided which prevents communication between material disposed on either side of the blade as the blade moves into proximity with the bottom portion of the casing. The seal prevents the transfer of material from one chamber to the next.
In some embodiments, it may be desirable to permit fluid to flow from chamber to chamber through the seal assembly as material is propelled through the screw conveyor. It is desirable on some occasions to change the porosity of the seal or to replace the seal with a different seal for use in a new application. It is also desirable to replace portions of the seal assembly which are damaged by contact with foreign objects as the material is transported or which are damaged by wear which occurs over time but which occurs in a particular segment of the seal assembly for one reason or another. In both of these cases, it is desirable to easily replace portions or the seal assembly without removing the entire auger from the machine.
Accordingly, scientists and engineers working under the direction of Applicants' assignee have sought to develop a seal assembly which extends between members capable of relative movement which is easily replaceable and which facilitates replacing damaged portions of the seal assembly.